Intel/AMD or Via x86 processors are supported by either the i386 or amd64 ports (..sometimes both), if you installed OpenBSD/i386, you must use packages compiled for that architecture.

You can confirm which architecture you're using via the uname(1) command:$uname -m

Please note; that the error you're seeing is likely related to the fact that you have not installed the appropriate X sets.. which many ports rely on for additional libraries (..freetype in this case).

FreeType is a font library, it is part of Xenocara in OpenBSD.. and several times people have posted on the mailing lists about being unable to install a specific library on their headless server/router that doesn't have the X sets installed.

Also; locate freetype.so.16.1 shows that it is in /usr/X11R6/lib, no ports are allowed to install libraries outside of /usr/local.

Another common failure is a missing X11 installation. Even if the port you try to build has no direct dependency on X11, a subpackage of it or its dependencies may require X11 headers and libraries. Building ports on systems without X11 is not supported, so if you insist on doing so, you are on your own to figure it out. For many ports, there are, however, "no_x11" flavored packages available, which you can install without needing X11 on your system.